Double Glazing

[lewisericeric]

Does anyone have double glazing that's NOT thermal break? 

 

I understand the technical definition of thermal break windows, I'm wondering what the actual difference is in terms of condensation performance in portholes. 

 

I'm having an issue with my boat builder being able to get thermal break windows to coincide with my build date and they're offering non-thermal break as an alternative. 

[IanD]

26 minutes ago, lewisericeric said:

Does anyone have double glazing that's NOT thermal break? 

 

I understand the technical definition of thermal break windows, I'm wondering what the actual difference is in terms of condensation performance in portholes. 

 

I'm having an issue with my boat builder being able to get thermal break windows to coincide with my build date and they're offering non-thermal break as an alternative. 

 

Double glazing is quite common in new boats, thermal break windows less so -- especially with portholes.

 

With portholes there's relatively little exposed frame, and unless the porthole itself is also thermal break (which I don't think any are) there seems little point having thermal break frames because the porthole itself (if opening) has more exposed metal than the frame.

 

When I talked to Ricky at Finesse about this (and both types were available) his view was that thermal break windows had some benefits (less condensation) but thermal break portholes were pretty pointless, just a waste of money.

 

Depending who your windows are coming from (Caldwells?) another thing to think about is that some finishes (e.g. heavy satin anodised) are not available on thermal break frames because the process involves heating them up and the plastic thermal break inserts won't take this.

[lewisericeric]

Thanks Ian, very helpful post. 

 

I don't understand the concept of 'less condensation' though which I keep hearing as surely with all double glazing condensation is eliminated anyway due to it being... double glazed? 

[Alan de Enfield]

1 minute ago, lewisericeric said:

Thanks Ian, very helpful post. 

 

I don't understand the concept of 'less condensation' though which I keep hearing as surely with all double glazing condensation is eliminated anyway due to it being... double glazed? 

 

You won't get condensation of the glass, but will still get it on the frame - UNLESS the frame has the thermal break

[Tracy D'arth]

1 minute ago, lewisericeric said:

Thanks Ian, very helpful post. 

 

I don't understand the concept of 'less condensation' though which I keep hearing as surely with all double glazing condensation is eliminated anyway due to it being... double glazed? 

Its not so much the glass that gives the condensation on double glazed units but the frame and surround. That is where the thermal break is included between the frames.

[TheBiscuits]

2 minutes ago, lewisericeric said:

Thanks Ian, very helpful post. 

 

I don't understand the concept of 'less condensation' though which I keep hearing as surely with all double glazing condensation is eliminated anyway due to it being... double glazed? 

 

The condensation forms on the coldest surface first.  In the case of double glazed windows this tends to be the frame, so you get just as much condensation but in a slightly different position.

 

Thermal break frames aren't as bad for this, hence their increased popularity.

[lewisericeric]

That's odd. I supposedly have thermal break double glazing on this boat (Caldwells) and I get horrendous amounts of condensation on the frame still. 🙄

[Hudds Lad]

2 minutes ago, lewisericeric said:

That's odd. I supposedly have thermal break double glazing on this boat (Caldwells) and I get horrendous amounts of condensation on the frame still. 🙄

Have you tried not breathing? That's where it all comes from you know. Start practicing now and you'll be able to go weeks in winter  

[Jen-in-Wellies]

Cooking is another thing to avoid. Not just steam from the simmering pots, but also from the burnt gas. Four molecules of water created for every molecule of propane.

[lewisericeric]

6 minutes ago, Hudds Lad said:

Have you tried not breathing? That's where it all comes from you know. Start practicing now and you'll be able to go weeks in winter  

Plenty of time for all that nonsense when I've passed on.

[Alan de Enfield]

1 hour ago, lewisericeric said:

That's odd. I supposedly have thermal break double glazing on this boat (Caldwells) and I get horrendous amounts of condensation on the frame still. 🙄

 

Well, now that three of us have told you why, you now know.

[David Mack]

9 hours ago, Hudds Lad said:

Have you tried not breathing? That's where it all comes from you know.

And don't shower either!

[Alan de Enfield]

Just now, David Mack said:

And don't shower either!

 

Or boiling the kettle, or using hot water to 'wash the pots'

 

 

[Ronaldo47]

On the positive side, if you are getting condensation on  your window frames, you will probably not be getting it somewhere else, such as in your cupboards, as moisture from damp air will condense on any surface at a temperature lower than its dew point.

 

While I have never seen any actual examples, some older books on building practice describe windows for kitchens and bathrooms where the inner surface of the lower glazing bar was provided with a gutter to catch condensation, which was drained away to the outside  via a brass tube extending through the frame.

 

This is the sort of arrangement that used to be used on the compartment stock of railway  trains, where the gutter was a brass inlay close to the glass. I always used to feel comfortable travelling in those trains in winter, as the cold single-glazed glass used to condense the water vapour from the passengers' breath, thereby acting  as a sort of air conditioning by removing excessive water vapour from the air. The later double-glazed carriages with no roof ventilators and hermetically-sealed doors always used to feel  unhealthily stuffy in  winter and were very Turkish bath-like with seemingly 100% humidity, although I never had anything to measure it with. 

 

So you might be better off living with some  window frame consensation.

 

 

Edited May 12, 2022 by Ronaldo47
typos

[Tony Brooks]

8 hours ago, Ronaldo47 said:

While I have never seen any actual examples, some older books on building practice describe windows for kitchens and bathrooms where the inner surface of the lower glazing bar was provided with a gutter to catch condensation, which was drained away to the outside  via a brass tube extending through the frame.

 

If you have a boat with windows I bet you have such an arrangement. Look at the bottom channel section and i most cases you will see holes draining condensation from the inner channel, under the glass and out of holes in the outer part of the section. Some makers now fit a fancy cover over the holes.

[blackrose]

With all all porthole boat (single glazed) I've never really found condensation on the frames to be a big issue like it is on boats with bigger rectangular windows. There's a fairly minimal amount of aluminum window frame and the condensation that does build up tends to stay there. Sometimes you get a few drips but nothing like the amount you get from bigger rectangular window frames.

[Murflynn]

19 hours ago, Jen-in-Wellies said:

 Four molecules of water created for every molecule of propane.

 

Jen, please consider if counting molecules in the air trapped in your boat really is a worthwhile activity, speshully now the boating season is upon us.

 

Is that an approximation or have you made rigorous checks including the air spaces behind the panelling and under the floor? 

 

 

.................   coat 

[Jen-in-Wellies]

11 hours ago, David Mack said:

And don't shower either!

Which has the added advantage of dissuading other people from visiting and breathing out water vapour inside your boat.

 

Quote

Jen, please consider if counting molecules in the air trapped in your boat really is a worthwhile activity, speshully now the boating season is upon us.

Counting molecules is a winter pastime, when I'm bored. In summer, there are enough doors and windows open that the extra air circulation means it is too easy to lose track of which molecules I've already counted.

Edited May 13, 2022 by Jen-in-Wellies

[GUMPY]

For the last twenty years I have had boats with single glazed windows and secondary double glazing and get no condensation on the frames or glass unless of course the magnetic strip holding the secondary pane has slipped / come unstuck.

It was a simple solution to a simple problem 

 

[Idle Days]

We find that using pothole stuffers overnight removes the condensation problem from that area. Just leaves the double glazed window frames to wipe each morning in cold weather.

[Slow and Steady]

2 hours ago, Loddon said:

For the last twenty years I have had boats with single glazed windows and secondary double glazing and get no condensation on the frames or glass unless of course the magnetic strip holding the secondary pane has slipped / come unstuck.

It was a simple solution to a simple problem 

 

Never seen a boat with steel windows - how does your magnetic strip work?

[GUMPY]

9 minutes ago, Slow and Steady said:

Never seen a boat with steel windows - how does your magnetic strip work?

It's a  magnetic strip coloured brown on the wooden surround of the window and a matching  steel strip on the double glazing.

You can just see it round the windows in this picture taken with the glazing down.

[Tony Brooks]

17 minutes ago, Slow and Steady said:

Never seen a boat with steel windows - how does your magnetic strip work?

 

The strip is self-adhesive as far as i know. One strip is stuck on the cabin side around the window aperture while another strip is stuck onto the double lazing. The two strips attract each other. You could, I suppose stick on strip to the window frame, but I suspect over time the condensation may make it fall off.

[Slow and Steady]

15 minutes ago, Loddon said:

It's a  magnetic strip coloured brown on the wooden surround of the window and a matching  steel strip on the double glazing.

You can just see it round the windows in this picture taken with the glazing down.

Doh - so obvious once it's explained! I might try that.

[GUMPY]

6 minutes ago, Slow and Steady said:

Doh - so obvious once it's explained! I might try that.

Don't forget to clean where the strip goes with isopropyl alcohol to remove any smoke deposits, silicone polish etc, makes the strip adhere better.

 

Edited May 13, 2022 by Loddon